Automatic and other gramophones



March 5, 1940. s, MANN 2,192,360

AUTOMATIC AND OTHER GRAMOPHONES Filed Sept. 21, 1938 Inventor 57-5.WVA/M ttqrneys Patented Mar. 5, 1940 UNITED STATES PATENT OFFICEAUTOMATIC AND OTHER GRAMOPHONES George Stanley Mann, Ipswich, EnglandApplication September 21, 1938, Serial No. 231,082 I In'Great BritainSeptember 29, 1937 8 Claims.

This invention relates to gramcphones ally but particularly to so-called automatic magazine grarnophones in which a number of records,stored in'a magazine or pile, are transferred in succession to aturntable for playing, the pick-up or tone-arm being automaticallyraised from a record upon termination of the playing thereof and, afterbeing swung over to the starting position, lowered on to the next recordto be played.

The primary object of the present invention is to provide improved andsimplified means for automatically raising the piclvup or tone-arm atthe requiredmoment and for allowing it to descend when a fresh recordhas: been deposited upon the turntable.

A further object of the invention is to provide means for giving acontrolled gradual lifting and lowering movement to the pick-up ortone-arm.

According to the invention a gramophone pickup or tone-arm mechanism ischaracterised by the incorporation of electro-magnetic means forauton'iatically raising the said arm under the control of electricalswitch means adapted to be operated by the horizontal movement of thesaid arm.

According to preferred embodiments of the invention the pick-up ortone-arm has-associated therewith a vertically movable rod which isadapted by its movements to raise and lower the arm, said rod havingassociated therewith an electric-magnetic means for imparting avertically rising movement thereto in order to efiect the raising of thepick-up or tone-arm. When the arm has been swung over to the startingposition the electro-magnetic means is de-energised in order to allowthe rod and the pick-up or tone-arm to descend.

According to a further feature of the invention and in order that thepick-up or tone-arm shall rise and fall with a gradual controlledmovement, it is associated with a damping means, for example a dash-potdevice. hereinbefore mentioned rod associated with the pick-up ortone-arm may carry a piston member adapted to work in a cylinder againsta fluid resistance.

In order that the invention can be fully appreciated one preferredembodiment thereof will now be described with reference to theaccompanying drawing wherein the single figure shows a verticalsectional elevation of a gramophone pick-up arm mechanism. 1

The pick-up arm I is pivoted at 2, for movement in a vertical plane,upon a rotatable bracket 3 supported upon the top board 4 of a gramo-For this purpose the is coupled with the upper end of a vertical rodt'formed of magnetic metal and disposed coaxially with the rotatablebracket 3 and. its

bearing. Said rod 5 is guided for vertical movement and also turningmovement within a guide sleeve 6.

The coupling between the pick-up arm I and the rod 5 is such thatsaidrod turns with the arm.

At a position below the top board l the rod 5 is provided with anenlarged portion 1 which constitutes a core for an electro-magnet 8 ofhollow or so-called pot form. It should be noted that thiselectro-magnet 3 is connected through the intermediary of the sleeve *5with the rotatable bracket 3 and therefore said magnet turns with thepick-up arm l and vertical rod -5.

The said rod 5 is also provided with another A enlargement 9 whichconstitutes an armature for co-operating with the electro-magnet 8 andbelow this armature the rod 5 carries an arm lit-provided. at its outerend with a stud I! adapted to is such that, when the pick-up reaches theusual run-01f groove of the record on completion of its playing, the armI0 is oscillated in a horizontal plane to effect energization of theelectro-magnet 8 and thus bring about an upward movement of the rod 5and the consequential raising of the pick-up arm I to lift the needle l2from the record indicated in dotted lines at l3.

De-energization of magnet 8 following deposition of a fresh record onthe turntable and return of the pick-up arm to its starting positionallows the pick-up arm to fall, thus to bring the needle I! into contactwith this fresh record. I

According to another feature of the invention and in order that thepick-up arm I shallrise and also fall with a gradual movement instead of.being caused to rise sharply by the action of the electro-magnet 8 andto fall suddenly by its own weight, means are provided for effecting adashpot controlled movement.

For this purpose the vertical rod 5 is extended below the switch arm l0and at its lower end carries a piston l6 workingin a vertical cylinderl1 adapted to contain oil or other fluid.

During the upward movement of the rod 5 under the influence of theelectro-magnet 8 the piston I6 is raised and fluid passes slowly to theunder side of the piston through one or more restricted passageways suchas that indicated at I8. Thus the rising movement of the pick-up arm Iis retarded and proceeds gradually and smoothly Furthermore upon thede-energising of the electro-magnet 8 the rod 5 and the pick-up arm Iwill fall and in falling move the piston l6 downwardly against theresistance of the fluid so that the lowering of the pick-up arm isretarded and the needle l2 lowered on to the record smoothly andgradually in order to commence the playing thereof. 7 i

In order to limit the descent of the rod E and its associated magneticcore 1 and armature 9 an adjustablescrew means is is provided in thebase of the dash-pot cylinder ll, the inner end of said screw meansbeing adapted to form an abutment for the lower face of the piston itAlthough it is to be understood that any desired suitable switchmechanism may be provided and adapted for operation by means of theswitch arm In, it is preferable that this switch mechanism be of thekind described in the specification of applicants co-pending Britishpatent application No. 26383/37.'

The invention is not limited to the precise forms or details ofconstruction described, as these may be varied to suit particular caseswithoutdeparting from the scope of the appended claims.

What I claim and desire to secure by Letters Patent of the United Statesof America is:'

1. A gramophone pick-up or tone-arm mechanism comprising a bracketrotatable in a horizontal plane, a pivotal connection between saidrotatable bracket and the tone-arm to allow the latter to be moved in avertical plane, a hollow electro-magnet supported by and rotatable withthe said bracket, a vertically movable rod extending through the bore ofthe hollow electro-magnet and concentric with the axis of rotation ofthe rotatable bracket, a connection betweensaid rod and the verticallymovable arm and a magnetic core on the rod for cooperation with theelectro-magnet so that upon energisation of said electro-magnet the rodis moved upwardly to lift the arm vertically about its pivotalconnection with the bracket and, upon the termination of suchenergisation the vertical rod will move downwardly to return the arm toits lower position.

2. A gramophone pick-up or tone-arm mechanism, as claimed in claim 1, inwhich the vertically movable rod extends through a rotatable guidesleeve to which the bracket is secured.

3. A gramophone pick-up or tone-arm mech-. anism as claimed in claim 1,in which the tone arm is mounted for turning movement and the verticallymovable rod is coupled by said lastnamed connection with the toneearmfor turn ing movement therewith.

A gramophone pick-up or tone-arm mechanism as claimed in claim 1, inwhich the tonearm is mounted for turning movement, and the verticallymovable rod is coupled by said lastnamed connection with the tone-armfor turning movable rod extends through a guide sleeve connected at oneend to the electro-magnet and at its other end to the bracket wherebysaid'electromagnet turns with the pick-up arm and the rod.

5. A gramophone pick-up or tone-arm mechanism as claimed in claim 1, incombination with means for damping the upward and/or downward movementof the vertically movable rod.

6. A gramophone pick-up or tone-arm mechanism as claimed in claim 1, in;combination with means for damping the upward and/or downward movementof the vertically movable rod, said means comprising a piston elementcarried movement therewith, and in which the vertically I by said rod atthe lower end thereof and a 00- operating cylinder containing a dampingfluid.

7. A gramophone pick-up or tone-arm mechanism as claimed in claim 1, incombination with means for damping the upward and/or downward movementof the vertically movable rod,

and adjustable means for limiting the downward movement of the rod. 8. Agramophone pick-up or tone-arm mechanism as claimed in claim 1, incombination with means for damping the upward and/or downward movementof the vertically movable rod, said means comprising a piston elementcarried by said rod at the lower end thereof and a cooperating cylindercontaining a damping fluid,

and adjustable means for limiting the downward movement of said pistonelement in said cylinder.

GEORGE STANLEY MANN.

